Could you @diizzy elaborate more on that? I think that ipq806x has still the old default of 100 Hz as the kernel frequency. Do you have experience in raising that value to either 250 or 1000 on this platform?
I have noticed some substantial gap between the targeted download speed in SQM and the actual download speed with R7800 (especially with simple/fq_codel, something like 90Mbit vs. 77 Mbit, while cake seems to provide better throughput). I did not see similar effects with my old WNDR3800, so I wonder if this is something special for ipq806x and if raising the kernel Hz would really help. Or alternatively, if something in the quite recent kernel bumps have caused performance regressions in general. I will probably need to test more thoroughly with "flent".
And I might test also with the increased kernel Hz frequency, as some of the other platforms seem have 250 as the default already now.
To expand the previous:
I have stumbled upon strange behaviour of R7800 with SQM using simple/fq_codel:
There is a significant speed gap between the set download speed limit and the realised download speed, as measured by flent.
With cake the same speed limit produces significantly higher download speed.
My old WNDR3800 (ar71xx) produces the same speed with cake and simple as R7800 with only cake.
Increasing the download speed limit by 10 Mb increases the actual download speed by maybe 7 Mbit/s, so the router is not hitting any real CPU or I/O performance limit.
It is almost like the simple/fq_codel would produce in ipq806x a realised download speed of some 75% of the set limit. With the old trustry ar71xx/WNDR3800 the speed gets higher, to near the CPU hardware limits.
This almost looks like there is some kind of calculation bug in the fq_codel code when compiled for IPQ806x (code base is arm_cortex-a15_neon-vfpv4 )
Any clues to what could cause this? How to debug?
Can router's automatic CPU frequency scaling (between 384-1700 MHz according to load) cause trouble for codel? But not for cake?
I don't use any qos, but I saw dd-wrt has the same issue, it uses kernel 3.18. You can try to set performance governor so it maxes CPU frequency without scaling and check if it has any affect
I suspect this issue is related with this: when you benchmark OpenSSL speed with "openssl speed sha256", you watch how it tests different packet sizes with 3 secs interval, but in fact it's sometimes not 3 secs but 2.97, 2.99, 2.95 secs and so on. I suspect that opensource is missing some driver that syncs clocks between subsystems in a soc
setting HZ=1000 means that you have a much finer granularity of schedulers and packet handling. I'm pretty sure that Cerowrt sets this by default and I know it's the recommended setting in FreeBSD (and default nowdays).
Thanks to dlizzy (in the other thread) I've decided to get NBG6817 because I found it for a very interesting price over here. 169$. it is way cheaper than r7800 here and since they have the same hardware that was an easy choice
I just didn't quite understand the flashing procedure for NBG6817.
it say:
For installation copy xx-mmcblk0p4-kernel.bin and xx-mmcblk0p5-rootfs-full.bin
to device. Then run:
cat xx-mmcblk0p4-kernel.bin > /dev/mmc0blk0p4
cat xx-mmcblk0p5-rootfs-full.bin > /dev/mmc0blk0p5
reboot -f
do i normally SSH to it or what do I miss here? and how to revert it back to factory if I will need it?
Thank you in advance.
Doesn't the Ath10K require closed firmware blob as well? Are Ath10K and mwlwifi THAT different with respect to openness. Neither has the openess of Ath9K.
[quote="okji, post:43, topic:80"]
Doesn't the Ath10K require closed firmware blob as well? Are Ath10K and mwlwifi THAT different with respect to openness. Neither has the openess of Ath9K.
[/quote]yep, ath10k includes a firmware blob as well. Neither is as fully open as ath9k.
Anybody think it is a good idea to avoid buying Ath10K and mwlwifi devices for now considering Ath9K is all that is going to receive support from the make-wifi fast initiative? I've had nothing but solid Ath9K performance and I'm wondering if there's anything to be gained by moving to Ath10K or mwlwifi if Ath9K is only going to improve in performance.
Ath9k is 802.1an only of course... If you want 802.11ac, Mediatek with mt76 is the most open 802.11ac hardware/driver combination around. There a few Mediatek devices that work nicely. I have an AC1300 D-Link DIR-860L rev B1 myself, e.g.
.> .. I have an AC1300 D-Link DIR-860L rev B1 myself, e.g.
@Borromini, Would you mind sharing a recent performance figure? I need a new router to replace my single core 400Mhz Buffalo as a VPN server. I found that my slow VPN speed is limited by the processor speed. Do you have any comment about its speed?
How fast is the mediatek CPU that is used in the dir-860l B1? What kind of LAN <-> WAN speeds is it able to get with traffic shaping (piece of cake) enabled? I am currently running a 200/40 Mbit internet connection and the Archer C7 I am using is showing a lack of CPU power in those cases.
